package day07;

import java.util.Random;

public class VerificationCode {
    public static void main(String[] args) {
        String code = generateVeriCode(4);
        System.out.println("验证码："+code);


    }//生成验证码
    public static String generateVeriCode(int len){
        String code = " ";
        char[]chs= {'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z',
                'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
                '1','2','3','4','5','6','7','8','9'};
        Random rand =  new Random();
        for (int i=1;i<=len;i++){
            int index = rand.nextInt(chs.length);
            code +=chs[index];

        }

        return code;

    }

}

